For the third year in a row, lawmakers appear uncharacteristically united in their opposition to the Defense Department’s request for another round of BRAC—the acronym for base realignment and closure—even though the process is based on a law Congress itself crafted back in 1990. The reason most lawmakers cite is that the last BRAC round, in 2005, was the costliest ever, not to mention a poor short-term investment: $35 billion in up-front implementation costs to save $4 billion annually in perpetuity.

But as the U.S. military becomes leaner, adapting to the realities of modern technology and geopolitics, we should continue to expect decreases in Army and Marine Corps end strength, the retirement of Air Force aircraft and the laying up of Navy cruisers. Given this downsizing, the cost of refurbishing existing bases and the limited resources expected to be available in the years ahead, we should question whether Congress’s opposition to the base cuts is prudent, or even defensible.

For one thing, BRAC 2005, which Congress approved at the time, was an anomaly: We were a nation fighting two wars with a ballooning defense budget, and the BRAC process became one of realignment—a building spree rather than cuts. Only 5 percent of U.S. base capacity—essentially acreage and buildings—was eliminated. In contrast, consider earlier iterations of the modern BRAC process that occurred as U.S. forces retrenched following the Cold War. The Defense Department estimates that in four BRAC rounds—1988, 1991, 1993, 1995—approximately 21 percent of the 1988 U.S. base capacity was eliminated. (Defense Secretary Frank Carlucci initiated the 1988 round before Congress passed its BRAC law in 1990.) These cuts made perfect sense given that from 1988 to 1995 the United States decreased worldwide active-duty end strength from 2.1 million troops to 1.5 million.

Today, as the Pentagon again shrinks its forces and asks for another BRAC in 2017, it admits the process would cost perhaps $6 billion up front. But it would also add $2 billion in perpetuity to the $16 billion in recurring savings from all previous BRAC rounds. The Defense Department claims excess capacity of about 20 percent, with the Air Force alone acknowledging 25 percent excess. These numbers are due mostly to obsolescence, improvements in operational efficiency, retirement of old systems and, perversely, the reorganization/consolidation actions that emerged from the 2005 BRAC round. The downsizing that’s already underway is, of course, reasonable given the Pentagon’s professed aim to prioritize weapons modernization, special operations and cyber security initiatives. If Congress fails to rein in the military’s rising personnel and benefits costs or reinstates the sequester’s spending caps, keeping excess bases up and running is also financially indefensible.

Gen. Norton A. Schwartz (Ret.) served as chief of staff for the U.S. Air Force from 2008-2012 and is president and CEO of Business Executives for National Security.

William F. Murdy is chairman of Comfort Systems USA and vice chairman of the board of directors for Business Executives for National Security.